The Russian Mosin Nagant Forum

Fired Milsurp and SELLIER and BELLOT (new ammo) today. Had a couple of missfirings with both. It fired every time the second attempt.
Is there such thing as a week firing spring or could there be another issue?

Thanks.

Have you checked the headspace and the firing pin protrusion?

Firing pin protrusion most likely. I've also seen some folks snip a turn or so off the firing pin spring in a misguided attempt to reduce trigger pressure.

I have checked both. They are good. (It barely passes the NO GO gauge but definitely passes the FIELD gauge)
The firing pin spring was not touched.....

2700fps wrote: ↑Wed Jun 12, 2019 8:40 pm I have checked both. They are good. (It barely passes the NO GO gauge but definitely passes the FIELD gauge)
The firing pin spring was not touched.....

With the trigger back and rifle empty, Pull on the cocking knob of another Mosin and compare the spring tension to yours.

2700fps wrote: ↑Wed Jun 12, 2019 8:40 pm I have checked both. They are good. (It barely passes the NO GO gauge but definitely passes the FIELD gauge)
The firing pin spring was not touched.....

Also just because the firing pin wasn't touched, doesn't mean that it's adjusted properly. Always better to check everything before you start throwing money at parts to fix it.

One of the major reasons I stick to surplus ammo besides the price is I have had inconsistent new ammo and yes some of it was S&B. Just because its new doesn't mean its good and always the same. Bill

S&B 7.62x54r wasn't the best new ammo I have shot. I seem to remember it chambering with some difficulty in my M91, but I didn't have any fail to fires. Try some different ammo if all else fails.

You did check firing pin protrusion? This is not done with headspace gauges.

I'd say to test some other ammo. You can still find surplus around (even small quantities, that you can test with, at gun shows. Also, Winchester makes some too that have always gone bang for me. Also PPU has some good stuff. I say those two because they have decent reloadable brass...

Yes. I have checked the firing pin with the tool that comes with every mosin.
I have fired both of these type of ammo through my other mosins without any issues.

Get a new firing pin spring, or just change it out with one from one of the other mosins as a quick check to verify. If it's protruding far enough then it would have to be how hard it's hitting the primer. I've had no problems with S&B in any of mine.